IBX: A Novel and Versatile Oxidant for Electrophilic Thiocyanation of Indoles, Pyrrole and Arylamines

Abstract

The direct thiocyanation of indoles and pyrrole with ammonium thiocyanate has been achieved using o-iodoxybenzoic acid (IBX) under mild and neutral conditions to produce indol-3-yl and pyrrol-2-yl thiocyanates, respectively, in excellent yields and with high selectivity. This method is effective even with N-substituted arylamines for the preparation of aryl thiocyanates.

Key words

o-iodoxybenzoic acid - electrophilic substitution - indoles - aryl thiocyanates - heteroaryl thiocyanates

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